man/journal-iterate-poll.c

   1 /* SPDX-License-Identifier: MIT-0 */
   2
   3 #define _GNU_SOURCE 1
   4 #include <poll.h>
   5 #include <time.h>
   6 #include <systemd/sd-journal.h>
   7
   8 int wait_for_changes(sd_journal *j) {
   9   uint64_t t;
  10   int msec;
  11   struct pollfd pollfd;
  12
  13   sd_journal_get_timeout(j, &t);
  14   if (t == (uint64_t) -1)
  15     msec = -1;
  16   else {
  17     struct timespec ts;
  18     uint64_t n;
  19     clock_gettime(CLOCK_MONOTONIC, &ts);
  20     n = (uint64_t) ts.tv_sec * 1000000 + ts.tv_nsec / 1000;
  21     msec = t > n ? (int) ((t - n + 999) / 1000) : 0;
  22   }
  23
  24   pollfd.fd = sd_journal_get_fd(j);
  25   pollfd.events = sd_journal_get_events(j);
  26   poll(&pollfd, 1, msec);
  27   return sd_journal_process(j);
  28 }